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Title: Simulation of acoustic agglomeration processes of poly-disperse solid particles

Abstract

This article presents the simulation of acoustic agglomeration of poly-disperse solid particles with the direct simulation Monte Carlo method. The modelled processes include the agglomeration due to the orthokinetic and hydrodynamic mechanisms, Brownian coagulation and wall deposition. The aggregates formed during the agglomeration process were characterised as mass fractal aggregates with an equivalent radius to estimate the average radius of the primary particles in individual aggregates. Acoustic agglomeration of fly ash with a lognormal size distribution and TiO{sub 2} particles with a bimodal size distribution was simulated and validated against the experimental data in the literature. It was found that the acoustic agglomeration process of solid particles could be represented with a modified version of Song's orthokinetic model and Koenig's hydrodynamic equation that account for the fractal-like morphology of the aggregates. The fractal dimensions of around 1.8 and 2.2 were obtained for the fly ash and TiO{sub 2} particles, respectively, consistent with the values reported for the aggregates in the literature. The poly-disperse nature of the primary particles is essential to the simulation; assuming mono-disperse primary particles leads to a significant underestimation of the agglomeration rate and the particle size growth particularly during the early stages of the acoustic agglomerationmore » process. Particle deposition on the chamber walls also has some effect on acoustic agglomeration.« less

Authors:
;  [1]
  1. Southeast University, Nanjing (China). School of Energy and Environment
Publication Date:
OSTI Identifier:
20885610
Resource Type:
Journal Article
Resource Relation:
Journal Name: Aerosol Science and Technology; Journal Volume: 41; Journal Issue: 1
Country of Publication:
United States
Language:
English
Subject:
01 COAL, LIGNITE, AND PEAT; ACOUSTIC AGGLOMERATORS; AGGLOMERATION; PARTICLES; PARTICLE SIZE; TITANIUM OXIDES; DISPERSIONS; MONTE CARLO METHOD; MATHEMATICAL MODELS; FLY ASH; FRACTALS; DISTRIBUTION; SIMULATION; BENCH-SCALE EXPERIMENTS; MORPHOLOGY

Citation Formats

Changdong Sheng, and Xianglin Shen. Simulation of acoustic agglomeration processes of poly-disperse solid particles. United States: N. p., 2007. Web. doi:10.1080/02786820601009704.
Changdong Sheng, & Xianglin Shen. Simulation of acoustic agglomeration processes of poly-disperse solid particles. United States. doi:10.1080/02786820601009704.
Changdong Sheng, and Xianglin Shen. Mon . "Simulation of acoustic agglomeration processes of poly-disperse solid particles". United States. doi:10.1080/02786820601009704.
@article{osti_20885610,
title = {Simulation of acoustic agglomeration processes of poly-disperse solid particles},
author = {Changdong Sheng and Xianglin Shen},
abstractNote = {This article presents the simulation of acoustic agglomeration of poly-disperse solid particles with the direct simulation Monte Carlo method. The modelled processes include the agglomeration due to the orthokinetic and hydrodynamic mechanisms, Brownian coagulation and wall deposition. The aggregates formed during the agglomeration process were characterised as mass fractal aggregates with an equivalent radius to estimate the average radius of the primary particles in individual aggregates. Acoustic agglomeration of fly ash with a lognormal size distribution and TiO{sub 2} particles with a bimodal size distribution was simulated and validated against the experimental data in the literature. It was found that the acoustic agglomeration process of solid particles could be represented with a modified version of Song's orthokinetic model and Koenig's hydrodynamic equation that account for the fractal-like morphology of the aggregates. The fractal dimensions of around 1.8 and 2.2 were obtained for the fly ash and TiO{sub 2} particles, respectively, consistent with the values reported for the aggregates in the literature. The poly-disperse nature of the primary particles is essential to the simulation; assuming mono-disperse primary particles leads to a significant underestimation of the agglomeration rate and the particle size growth particularly during the early stages of the acoustic agglomeration process. Particle deposition on the chamber walls also has some effect on acoustic agglomeration.},
doi = {10.1080/02786820601009704},
journal = {Aerosol Science and Technology},
number = 1,
volume = 41,
place = {United States},
year = {Mon Jan 15 00:00:00 EST 2007},
month = {Mon Jan 15 00:00:00 EST 2007}
}
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